Lock-stitch sewing-machine.



F. W. MERRGK.

LO'GK STTCH SEWING MACHINE. APPLICATION FILED 11:13.27, 1905'.

Patented Nov. 2, y19.09.

' 3 SHEETS-SHEET 1.

S @y QW. 2;-, QUT/Sw@ Znvezzon E. W. ME'REI'GK.

LOGE STITGE Smm@ meals.

APPLICATION FILED FEB. 27, 1905,

939,1 52. Patented Nov` 2, 1909.

3 SHEETS-SHEET 21 'E'. W. MERRICK.

LOCK STITGH SEWING MACHINE.

APPLICATON FILED FEB. Z7, 1905.

Batam-mmv. 2. m9.

74761622 ess e5:

UNITED sTATEs PATENT oEEioE.

FRANK W. MERRICK, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO UNION LOCK STITCH COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

Loox-STITCH SEWING-MACHINE.

Specication of Letters Patent.

Patented Nov. 2, 1909.

Application led February 27, 1905. Serial No. 247,420.

to the accompanying drawin Figu chine containing one embodiment of the invention, the said gure showing only the parts which are required to be shown in order to clearly indicate the nature and relations of the invention. Fig. 2 is a view showing certain of the devices of Fig. 1, partly in vertical transverse section. Fig. 2a is a detail plan view of presser 32 and its supporting means. Fig. 3 is an end elevation of the parts which are shown in Fig. 1, looking from left to right in Fig. 1. Fig. 4 is a view in vertical section on the plane indicated by the dotted line 4, 4, Fig. 1, looking in the direction indicated by the arrows at the ends of such line, the pressersupport and spring-presser being brokenA away to show parts which otherwise would be hidden. Figs. 5 and are plan views of the upper end of the post, with the worksupport removed, showing chiefly the shuttle or loop-taker and'loop-spreader in two different positions. Fig. 7 shows the shuttle, detached, in lan.

Having re erence to the drawings,por tion of the xed overhanging head of the frame of a sewing-machine is represented at 1, Figs. 1 and 3. A work-support is shown at 2, Figs. 1 to 4, the post carrying the said work-support being designated 3, and the lower portion of the fixed framework of the machine being indicated at 4, Figs. l to 3, the said post being connected with the said portion 4. An awlis partly shown at 5, Figs. 1 and 3. A straight hooked needle is shown at 6, Figs. l, 2 and 3, a portion of the needle-bar 7 by which the said needle is carried being shown in the said figures. The awl-bar, the actuating connections therefor, and the guides for the awl-bar and needle-bar, have been omitted from the drawings, not being necessary to i be shown for an understanding of the' in*- vention itself. They may be in practice off re 1 of the drawings represents in- 4front elevation a portion of a vsewing-inaany approved and suitable character and arrangement. 'Ihe means by which the awl-bar and awl, and the needle-bar and needle, are .actuated may vary in practice. Preferably continuously rotating cranks. are employed for the purpose, because of the absence of noise and vibration at high speed, and the small amount of wear and tear. A.- needleactuating crank-motion is shown in connection with the rotating shaft 8, which latter is mounted in bearings within the lower portion 4 of the fixed frame-work 'of the machine, the said crank-motion ,comprising the disk 9 fast upon the said .shaft 8, `the crank-pin carried by the said disk at 10, Fig. 3, and the connecting-rod, link, or pitman 11,` having one extremity thereof applied to the said crank-pin and the other extremity thereof joined tothe needle-bar 7 by means of a pin or stud 12. A threadguide for laying the upper or needle-thread into the open eye of the needle is shown at 13, Figs. 1 and 3, a thread-linger at 14, a presser-foot` atl 15, and a presser-bar ,at 16, YThe devicesfor operating the thread-guide and thread-finger, and for automatically raising and lowering the presser-barfand presser-foot,- Imay be of any approved and suitable character, as also may be the pro- By unscrewing the said screws the said hook or point may be removed andI either repaired and again attached, or replaced by a new one. The particular loop-taker shown in the drawings is a shuttle although this is notl essential in the case of the embodiments of some of the features of the invention, and is formed with a central thread-containing cavity, it preferably being provided within the said cavity with a tubular post 173, Fig. 2, upon which is or may be fitted a bobbin 174 serving in practice as a carrier for the los Second yor under thread. The loop-taker orv otlonar t carrie .by t

, of the machine. The gearing by which the loop-taker or 'shuttle is driven is roportioned 4'to cause the same to make a p urality of'rotations, two in the present instance, to each complete reciprocation of the needle, in order to enable one stitch tobe formed and completed before the needle renters the material which is being operated upon, preliminary to beginning the formation of the next succeeding stitch. l

At one point in the rotation of the looptaker or shuttle the loop-takin point or hook thereof intersects the path o the needle, as'

indicated in F igs. 1 and 2, the said point or hook passing the hooked end of the needle as the latter extends the loop of upper thread which has been drawn thereby through the material being stitched. In this mannerthe c tip of the said vpoint or hook is caused to enter the said'loop With'the loop-taker or.

shuttleworking at the same side of the materialy with the vertically-reciprocating straight hooked needle, and with the point or hook of the said loop-taker or shuttle Vlocated at the side of the latter at ywhich the needle is situated and intersecting at one point in its rotation the path of movement of the needle as just referred to, for the purose of entering the loop' of thread whichf as been drawn by the latter, it is necessary to taklng point or hook of the loop-taker or shuttle with the needle, needle-holdeigxor dneedle-bar as the said point or hook is carried around past the latter parts at the op. posite `point in the rotation of the loop-taker or shuttle. For this purpose, I cause the loop-taker or shuttle to rotate in a position corresponding with a plane that is slivhtly inclined or oblique with respect to the irection in which thestraight hooked needle 6 and its needle-.bar 7. reciprocate. This is illustrated by Figs. 1 and 2. Thereb at the said opposite point in the rotation o the loo -taker or shuttle the point or hook passes entirely at one side of the path of the needle,

needlevholder, and needle-bar, and thus clears the latter. The loop-taker or shuttle 'stands at an inclination o r Obliquity with respect to the intermediate or carrier-gear 13. 'taut this indication or Obliquity is so Slight; ltdfmsriwiect the driving relations. between the geaziuteoth with.'` 'which rovide against engagement of the loopsaaise the loop-taker or shuttle is formed or rovided and the teeth of the said interme iate or carrier-gear 18. Securing the above clearance by means of the inclination or Obliquity of the rotating loop-taker or shuttle has the especial advantage that it enables the required timing of the shuttle and needle with relation to each other to be secured in convenient manner with a shuttle which is actuated by driying connections rotating the same at a uniform rate of s eed, and with a needle which is actuated y means of a crank. The employment of mechanism acting to produce dierential or variable lspeed of the shuttle and needle operates to cut down the speed, especially in machines for heavy work.

The loop-taking point or hook of the looptaker or shuttle is constructed with an outer fiange 172, which passes to the outer` side of the hooked end of the needle as the said point or hook enters the loop which is held by the needle. The acting tace vof the forward portion of the said point or hook, see more particularly Fig. 3, is `formed at an incline or angle which, in the continued ad- ;vancing movement of the loop-taker or shuttle after the said point or hook has entered Within the said loop of thread, operates to extend such loop gradually in the direction in which the needle moves while withdrawing from the material being stitched. The said incline or angle is such that in the rotation of the loop-taker or shuttle it gains on the descending needle until it presses or sheds the loop out of the open eye of the moving needle.

In order to enable the loop-taker or shuttle to be rotated continuously with smoothness and without rattle by means of a single driver in gear-engagement therewith, I provide the same with a continuous or'unbroken circular series of teeth 17 5, and locate in an interval or space of normal width between twol of the said driving teeth the mouth or entrance of the slot 176, extending trans` versely across the face of the loop-taker or shuttle, within which the loop drawn by the needle is received and held as the loop is carried around the loop-taker orshuttle by the rotation of the latter. The teeth 175 are normally and uniformly spaced at and adjacent the said slot. The use of two or more gear-drivers, as required when a space corresponding to two or more teeth is left adjacent the slot, is obviated, as well as the rattle, etc., which 'are incident tothe action when such space exists.

For the purpose of enabling a close adjustment to 'be effected of the timing of the movement of the hook or oint of the looptaker or shuttle with relation to that of the needle-bar and needle, provision is made for adjustment of the lshuttle-driving gearing with relation to the needle-actuating crank.

nog

This provision is made in the present instance hy mounting the gear 19 u on shaft 8 with capacity for line angular s 'ft with respect to the needle-actuatingcrank-10,the said gear being fixed in the desired angular position by means of securingscrews 191, 191, which pass through segmental slots 192, 192, which are formed in the crank-disk 9 into threaded holes that are tapped in the web of gear 19.

At 20 is a spreader by Whiclrthe loop of upper thread drawn by the needlev isv rcstrained from being carried forward by the rotating shuttle, and also is stretched across the face of the shuttle so as to enter the slot 176.1 The said spreader is formed, the presentL instance, as a bent or elbewed armY working in a horizontal plane lietweenV the loop-taker or shuttle and the work-support 2. It is mounted upon the upper portion of theY post 3 by means of the pivot 21, which is located adjacent one side of theloop-taker or shuttle. For the purposefof operating thc spreader, it is furnished-with a gear-segment 22, Figs. 2, 5, and 6, the teeth of which are engaged by those of an endwise reciproeating rack-bar 23. The latter is fitted toV ways upon the upper end of the, post- 3, and is in operative engagement with the upper arm of a lever 24. The said lever is mounted pivotally upon'the stud 182, itslower arm being furnished with a roll 25, for engagement with the cam 26 upon the shaft 8. The said roil is held in contact with the periphery of the said'eam through the tension of an expanding spiral spring 27 contained TWithin a case 28 with w iichilre fixe-d frame of the machine is provided, the pressure of the spring being 4transmitted to the lever by means of a pin or plunger 29 Working within the said case. In operation, the spreader is caused to enter the loop of upper thread after the loo -taking point or hook'of the loop-taker or s uttle has entered such loop and partially opened the latter. It thereby is caused to en age Withone side of A the loop so as to restrain the latter from being carried around with the rotating looptaker or shuttle. By the swinging `movement of the spreader the loopY 1s extended i transversely across the face of thefloop-taker or shuttle Within the slot 176. `In order to give time for slipping the thread into the slotI as'the shuttle rotates, aswell Aas facilitate the entrance of the threadfthe narrow mouth or entrance of the slot is made with an f inclination rearward and transversely from the loop-taking point or hook, as shown drivin -teeth of theloop-taker or shuttle are forme inclinedor helical, as shown. The teeth of the intermediate orcarrier-gear 1-8 are also inclined or helical to inatch with those of the loop-taker or shuttle,l as shown by Figs. 1 and 2. To balance the end-thrust inone direction that is occasioned' by the intermeshing'of the inclined or helical driving-teeth of the loop-taker or shuttle with those of the intermediate or carrierear 18,

carrier-gear 181 are inclined in the reverse direction with relation to the teeth of gear 18, those of gear 19 being suitably formed for coaction with the teeth of the gear 181, as shown in Figs. 1 and 2.

tially upright rotating loop-taker or shuttle side hy side with respect to the needle and needle-bar, I arrange the opening oi the posite that at which the needte-har, ne

in order that unobstructed by the needle-barand needle,

an empty bobbin, inserting a. filfed one, threading-up,l etcr This arrangement of the r:aid opening enables the said operations to in'themachine. The under thread issues from the said cavity at the side of the looptalter or shuttle farthest trom the needlebar and needle, and after bending around the edge or rim of such cavity passes translast stitch inthe Workyas shown in Fig. 2. The said edge or rim is continuous and con-v stitutes an annular thread-guiding sar-'face around which the under thread renders in passing` from the source of supply to the portion of the under threadextending from the source of supply to the work is wholly clear of the path of rotation of the look-taking point-or hook of the loop-takerpr 4shuttle, and cannot` become caught bythe said point or hook. Thereby the employment of aV supplemental device 'for preventing the Vunder thread from being picked u by the point or hook andsewed in is ren ered unnecessary. The required tension of the under thread is secured by means of a tension disk 30, the circuiar rim of which compresses thesaid thread againstY the continuous or annular margin of the thread-containing cavity. The :said tension-disk is conveniently supby means of aY central pin or spindle projecting therefrom and fit-ting within. the bore of the central spindle 173. It? is'fs'ubi means of which its rim is pressed towar the margin of. the thread-containing cavity- Herein the said sprin is shown at 31, Figs. 2 and 2, it being a at or leaf-spring and @n account of the location of the substan- I thread-containing cavityY of the said looptaker or shuttle; at the side of the latter gg i' rjected to the tension of a suitablefspr'in by f the teeth of the companion interme iate or and loop-taking point or hook, are located, fti'ee access tothe said cavity,-

may be had for the purpose of taking-out l bev performed without removal of the looptaker orV shuttle from its werking positionV versely across the loop-taker or shuttle to the,

stitch-dimming. point in the machine. The

ported in Working position, as, for instance,

having connected therewith impresse;- 325 the 13e `convex face of which bears against the-outer face of the tension disk at the center vof Athe latter, which in this case coincides with the center of rotation of the loop-taker or shuttle. The support 33, Figs. .1, 2 and 2* to which the spring-presser is attached is hinged `at 34 to the portion 3 of the iixed frame-work of the machine, and is capable of being swung with the springnpresser into a position which, as indicated by dotted lines in Fig. 2, permits free access to the tensiondisk, bobbin, and thread-containing cavity.

The said hinged support is mainly broken away in Fig. 4. It is held in its closed normal working position, with the springpresser in contact with the tension-disk, by

means of a spring-latch 35l which is applied to the portion 3 of the frame-work.

The ortion of under thread which extends a ove the loop-taker or shuttle on its way to the work is engaged by the spreader, and occupies normally a position within the Velbowthereof.. Thus both threads are held from boing vcarried around by the rotation oi' the loop-taker or shuttle.. l

For the purpose of permitting the under `th-1read to slacken or relax as the take-up acts to set the stitch, so as to allow the said thread to be drawn up into the hole 1n the material which is bein stitched, the heel or butt 78, Fig. 7, of t e shuttle isrounded awayat the forward side .of slot 17 6. The rounded swell 1.79 immediately lfollowing the said slot as it passes under the under thread acts to reinstate the tension thereof just previo-.xs to the extreme of the takeup y action, thereby holding the under thread against the final pull on the uplper thread in setting the stitch. Thereby t e machlne is enabled to set atighter stitch without causing the under thread to cut intor the lower surface of the material being stitched, and a tighter tension may be carried without causing the material to be cut into or either thread to be broken. I do not claimthese features the shuttle herein, as they will angle to the line of reciprocation of the.

- needle, vand driving devices operating to cause a plurality of continuous rotations of the loop-taker inlone direction to each recp'- rocation of' the needle.

2. In a sewing machine,

' with a needle, of a loop-taker having an unbroken circular series of gear-teethvall disposed in the same plane extending at right angles .to the axis of the loop-taker, the said lthe combination l loop-takerbeing formed with a transverselyextending slot for the loop of needle-thread the entrance to which is wholly contained in p' loop of `needle-thread, the entrance to which is wholly contained within the transverse interval of normal width between two of such gear-teeth, and a single rotating gearwheel engaging with the said series of teeth to rotate the loop-taker. v y

4. In a sewing-machine, the combination withA a needle, of a loop-taker havi a circu lar 'series of inclined gear-teeth, an receivthe transversely-extendinr portion of a loop formed by the needle, and' driving means eny gaging with said inclined gear-teeth to rotate the loop-taker. y v

5. In a sewing-machine, the combination vwith a needle, of a loop-taker having a circular series of inclined gear-teeth, and receiv- 1ng in an inclined space between; twoof the said teeth the transversely-extending portion of a loop formed by the needle, of a riving gear-wheel also having inclined gear-teeth. f

6. In a sewing-machine, the combination with a needle, and the gear-driven toothed loop-taker having between two of the teeth thereof a thread-receiving depression located vwithin the diameter of the toothed periphery of the loop-taker, of the loop-spreader o ry ating to pass the loop of thread forme by the needle into the said depression.

7. In a sewing-machine, the combination with a needle, and the gear-driven 'toothed loop-taker providedat one side thereof with a point which enters the loop of thread formed by the needle, and having between -two of the teeth thereof a vvthread-receivin depression located within the` diameter o` the toothed periphery of the loop-taker, of( the loop-spreader operating to pass the loop of thread formed by the needle into the said depression.

8. In a sewin machine, the combination with a needle, tie loop-taker having a circular series ofy inclined gear-teeth,'and driving means engaging with said gear-'teeth to rotate the loop-taker, of a spreader o erating to cause the loopof threa formed y the needle to extend t rough the inclined slot between two of the said gear-teeth.

9. In a. sewing-machine, the combination with a needle, and a rotary loop-taker having a point which enters the loop formed by the needle and partiallylopens the same, of a spreader entering the loop after having been thus partially opened and extending it 'lng in a space between two ofthe said teeth 'mmm across the peripheral rim of the loop-taker and into the throat of the latter,

I0. In a sewing-machine, the combination with a needle, and a rotary loop-taker having a thread-receiving depression aeross the widtlrthereof, and having also a point which enters the loop formed by the needle and artiall opens the same, of a spreader entering the oopY after having been thus partially opened and extending it within the said depression.

11. In a sewing-machine, the combination with a needle, and a rotary loop-taker hav-Y ing a point whichY enters the loop formed by the needle and partially opens the same, of a spreader entering the loop after having been thus partially opened, restraining the same from forward movement, and spreading the same across the peripheral face of the loop-'taker and into the throat of the latter.

122 In a sewin -machine, the combination with a needle, and a loop-taker, of a spreader for the loo drawn by the needle, restraining-the sai loop and the interlocking thread from forward movement.

13. In a sewing-machine, the combination with a needle, and a loop-taker, of the elbowed spreader engaging with the loop drawn b the needle and spreading such loop across the face of the loop-taker, and also operating to restrain the said loop and the interlocking thread from forward movement.

14. Ina sewing-machine, the combination with a needle, and a rota loop-taker havinga point which enters t e loop drawn by the needle and artially opens vthe same, of a spreader for t e said loop, extending the latter across the peripheral face of the shuttle, and restraining the said loop land the interlocking thread from forward movement.

15. In a sewing-machine, the combination with a hooked needle, of a rotating loop-l taker provided with a lian ed loop-taking portion passing over the en of the needle,

.making point.

and having an incline which ress thefl'oop from the open eye of the ne e; .A

16 in a sewing-machinerthe combination with a hooked medie; of a rotating looptaker provided a anged loop-iaking-i portion passing over the end of the receding -v needle to vshed* thealoop past the eye of the 1 needle, and having an incline which presses Y taking pointer hook next the needle-bar and needle, and its thread-containing eavity and thread-delivery-openin on the siderremote therefrom and lateral y remote from the line of stitching, the peripheral rim of the shuttle operating upon the portion of thread extending by the saine laterally to the stitchniaking point to deflect such the path of the said loop-ta hook.

18. In a sewing-machine, the combination with the needle, and the reeiprocatin needlebar, of the-rotating shuttle arrange side by side with respect to the needle and needlebar,v the said shuttle having its thread-delivery opening at the side thereof o posite that at which the needle and needle-liar are located and having at such side around the said opening an annular thread-guiding surface around which the under thread renders in passing from the source of supply to the stitch-'forming point in the machine, the thread extendin from the said surface across the top o the shuttle to the stitchg point or In testimon whereof I aflix my signature in presence o two witnesses.

' FRANK W. MERRICK. Witnesses:

Cms. F. RANDALL, EDITH J. ANDnRsoN.

ortion out of 

